Unfortunately, Magix.info is not available in French language at this point, but I think the answer to your question is easy: Website Maker produces Flash-based websites. The back and forward navigation buttons in your web browser don't have the same effect here as they do when navigating through the individual pages of HTML-based websites. For your browser the entire Flash website is one single page. Therefore, when you use the back button, you're leaving your entire site again.